Biking is not going to do any significant "damage." In fact, it will probably be good for you if you workout as active recovery.

This is like worry about things like this:
"if i don't stop my working in 45-60 minutes..... will my body become catabolic and lose muscle?"
"if I don't get carbs and protein post workout, how much will I be hurting my gains?"
"How much cardio does it take to lose muscle mass?"

Um, no. Stressing about whether you're going to become catabolic is going to be more catabolic than actually doing the workout. AKA it's nothing to worry about.


If you're still worried then do this. Bike it in intervals... .5-.75 miles as fast as you can, .25-.5 mile recovery. Or as I said previously take it as active recovery.